Letter exchanges

Letter exchanges indicate a certain letter in a piece of fodder and instruct the solver to replace it with another to help form a part or all of the answer word.

Letter switch indicators prompt the solver to exchange a letter in a word for another one which has been indicated separately. Here are some examples:

To get RUM to become RUN the setter needs to indicate that M must be swapped for N and so may write:

rum to prefer knight to man ...

... here, the letter switch indicator is TO PREFER. So RUM prefers N (one of the abbreviations for a knight in chess) to M (the abbreviation of man). And so RUM becomes RUN.

To get RUM from RUN the setter may spot that it is the last letter which needs changing and so use a switch indicator such as:run to make last mass ...

... the letter switch indicator TO MAKE LAST means the solver makes the last letter of RUN an M (the abbreviation of mass). And so, RUN becomes RUN.Any words that fairly lead the solver to the switching of letters may be employed. Here are some more examples:

Letter switch indicators - WITH X FOR Y/WITH A CHANGE OF HEARTAgain, the clue being in a down or across position will affect the indicator being used.